Screening-machine.



No. 891,821. PATENTED JUNE 30, 1908. R. P. CUNNINGHAM. SCREENING MACHINE.

APPLIOATION FILED MAY 3. 1907.

I. In l valve UNITED. ST TES PATENT OFFICE.

Roam P. GUNNINGYIIAM,

OF HOLYOKE, MASSACHUSETTS, ASSIGNOR TO INTERNATIONAL STEAM PUMP COMPANY, OF NEW YORK,.N. Y., A CORPORATION OF NEW JERSEY.

SCREENING-MACHINE.

Patented June 30, 1908.

Application filed May a, 1907. Serial No. 371,571.

To all whom it may concern:

Be it known that I, ROBERT P. CUNNING- HAM, a citizen of the United States, residing at Ho1yoke, county of Hampden, and State of Massachusetts, have invented certain new and useful Improvements in Screenin -Machines, fully described and re resented 1n the following specification and t e accompanying drawings, formin a part of the same.

This invention re ates to an im roved screening machine, which is especia ly intended as a sand screen or riddler, although capable of use for other purposes, the especial object of the invention being to secure a better screening action than in previous sand screens, and further to provide a simple and durable construction ca able of operating efficiently at a highs cc and which shall be reliable in action am avoid danger of stopp or a full understanding of the invention, a detailed descri tion of a sand screening machine embodying all the features of the same in their preferred form will now be given in connection with the accompanying drawings forming a part of this specification, and the features formingthe invention then specifically pointed out in the claims.

In the drawingsFigure 1 is a side elevation, partly in section. Fig. 2 is a planview partly in section. Fig. 3 is a vertical section of the screen actuating mechanism.

Referring to the drawings, A is the screen holder consisting of a circular frame receiving the removable screen B, and mounted upon arms 0 which are ivoted to their supports at 10, and pivota y connected to t e screen holder at 11 so as to rock on the supports as the screen reciprocates. The pivot 10 is shown as a ivot shaft rocking in brackets 12 on triangufar screen stand Dwhich sup ports the engine by which the screen is actu ated, but it will be understood that any other form of support for the rocking arms and screen holder may be used.

The screen holder A is connected to the reciprocating iston rod 13 of piston e moving in motor cy inder E, the cylinder and piston forming a double acting direct acting reciprocating engine, which may be actuated by steam, com ressed air or othcrsuitable motor fluid. The motor fluid is supplied to the engine through ports 1, 2 and exhausted through cove 3, which are controlled by the 6 shifted by the auxiliary piston 5 in the valve lever auxiliary cylinder F, which auxiliary piston is shown as connected directly to the valve 6, and controlled by the auxiliary valve 4 which controls the admission and exhaust of steam to opposite ends of the auxiliary piston 5, for moving it in opposite directions, as usual in such constructions.

The auxiliary valve 4 is actuated by the valve rod 7 provided with the usual tappets 8 engaged by the block 9 on valve lever j, so as to move the auxiliary valve in, opposite directions to the movement of the iston e, at the ends of the engine stroke, as t e block 9 engages one or the other of the tap ets 8,

being actuated from t 1e piston rod 13. T 1e piston rod 13 and valve rod :7 are supported and guided in guide 14 formng one end of the casing G, as shown.

The operation of the construction will be understood without detailed descri tion, the shifting of the main thrown piston'5," controlled by the auxiliary valve 4, securing a quick positive throw of the engine piston e, and a positive jerky movement 0 the screen B which, in connection with the swinging movement of the armsC, secures a screening action, which in practice is found efficient and an important improvement on previous screenmg movements. The positive throw of the screen in both directions by the double acting direct acting engine assures reliability of action and avoids danger of stoppage.

It will be understood that, the invention is not to be limited to the particular form of valve mechanism shown, nor to the detail.

form of other parts of the'structure, but that modifications may be made without depart ing from the invention.

What I claim is 1. The combination with a screen holder, of pivoted rocking supports for the holder, a stationary double acting direct acting engine having its piston connected to the screen holder for reci rocating the holder, a fluid thrown valve or said engine, an auxilia valve cc: itrolling the fluid supply for said fluid thrown valve, and connections between the auxiliary valve and the screen holder for iositively operating the auxiliary valve from and in unison with the screen.

2. The combination with a supporting frame, of a double acting direct acting engine rigidly mounted directly upon said frame, ascreen holder mounted on'pivoted valve 6 by t e steam rocking supports at one side of the engine, In testimony whereof, I have hereunto set the piston rod of the engine being connectegl my hand, in the presence of two subscribing directly to the screen holder, and valve dewitnesses.

vices for controlling the movements of the ROBERT P. CUNNINGHAM. 5 engine iston including a valve actuated Witnesses:

ositive y from and in unison with the screen NELSON W. HART, older. ALBERT F. 131212. 

